The present invention relates in general to liquid filtering and purifying and pertains, more particularly, to a device including means for filtering and purifying used engine coolant in order to produce a concentrated portion for disposal and a purified portion intended for reuse. The purification device of this invention is an improvement over the conventional filters which rely on mechanical separation or require the breakdown and separation of the used coolant into constituent parts prior to recovery.
With the conventional filter device it is generally necessary to first separate an emulsion before further separation. For example, recovering surfactant from an oil, water and surfactant emulsion may require pretreatment of the emulsion with chemicals followed by reverse osmosis. Other conventional devices use mechanical and chemical purifying processes. Coarse and fine filters have been used to remove foreign matter and activated charcoal filters have been used to remove bacteria.
Other conventional approaches include chemical reactions resulting in a precipitate or a phase change used to remove water, for example, by freezing. Backwashing, flushing and multiple mechanical filters are additional conventional approaches.
Conventional filters and purifiers actually may not concentrate an impurity, thereby often leaving a large volume of the impurity to be disposed of in a land fill or through an oxidation process, such as by incineration. Most disposal techniques have similar drawbacks, including limited number and volume of dump sites or land fills available for disposal and the expense of disposal which is typically directed proportional to the volume of material to be disposed.
Accordingly, it is an object of the present invention to provide an improved purification device and method that is adapted to remove impurities from a coolant mixture of ethylene glycol and water. With the purification device and method of this invention it has been found that the impurities are removed from the used coolant and concentrated to reduce the volume and thus the cost of disposal.
Another object of the present invention is to provide an improved purification device and method to reduce dissolved solids and in particular chlorides and sulfates.
A further object of the present invention is to provide an improved purification device and method to purify used engine coolant in order that the purified coolant may be reused. It is expected that the used coolant will be approximately 90% reclaimed with the impurities trapped and collected in either at least one disposable filter or concentrated in the approximately 10% retained after purification.
Still another object of the present invention is to provide an improved purification device and method that reduces waste disposal volume and the cost of engine coolant. The device and method of this invention is characterized by maintaining substantially the same water to ethylene ratio in a purified engine coolant as in unused engine coolant.
Still a further object of the present invention is to provide an improved purification device and method for reducing chlorides, sulfates and conductivity of used engine coolant. A concentrated waste by-product is removed leaving a clarified engine coolant intended for reuse as an engine coolant.
Another object of the present invention is to provide an improved purification device utilizing an improved purification method that is adapted for portable use. The portability of the device should allow small and large users alike to take advantage of this invention.
A further object of the present invention is to provide an improved purification device and method that includes reusable purification components and elements. The present invention may be operated for extended periods without replacing components, thereby reducing potential down time of the device.